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1.
Research advances of un-symmetric constitutive equation of anisotropic fluid,influence of un-symmetric stress tensor on material functions,vibrational shear flow of the fluid with small amplitudes and rheology of anisotropic suspension were reported.A new concept of simple anisotropic fluid was introduced.On the basis of anisotropic principle,the simple fluid stress behaviour was described by velocity gradient tensor F and spin tensor W instead of velocity gradient tensor D in the classic Leslie-Ericksen continuum theory.Two relaxation times analyzing rheological nature of the fluid and using tensor analysis a general form of the constitutive equation of co-rotational type was introduced.More general model LCP-H for the fluid was developed.The unsymmetry of the shear stress was predicted by the present continuum theory for anisotropic viscoelastic fluid-LC polymer liquids.The influence of the relaxation times on material functions was specially studied.It is important to study the unsteady vibrational rotating flow with small amplitudes,as it is a best way to obtain knowledge of elasticity of the LC polymer,i.e.dynamic viscoelasticity.For the shear-unsymmetric stresses,two shear stresses were obtained thus two complex viscosities and two complex shear modulus(i.e.first and second one) were introduced by the constitutive equation which was defined by rotating shear rate introduced by author.For the two stability problems of fluid,such as stability of hydrodynamic flow and orientational motion,were discussed.The results show that the polymer suspension systems exhibit anisotropic character.The PNC systems can exhibit significant shear-thinning effects.For more concentrated polymer nano-suspensions,the first normal stress difference change from positive to negative,which is similar to LC polymer behavior.  相似文献   

2.
针对民办高校所需办学经费无国家财政拨款,全部为自筹资金的现状,分析了形成当前民办高校融资难的原因,既有信贷政策、银行方面的因素,也有民办高校自身的因素.提出民办高校要生存,要发展,光靠举办者投入或捐赠以及每年的学费收入是不够的,还需要积极拓展更多融资渠道解决办校融资难的问题.  相似文献   

3.
根据细粒磁性物回收工艺中需要使用预磁器的要求,研究预磁器的工作时序、充放电回路的电器元件特性和电路电压、电流特征.设计的电磁预磁器磁场强度高,能耗低,性价比高.对预磁化电路展开理论计算和推导.首次提出脉冲振动预磁器系统结构,将RLC电路振荡波形转变为振动波形,形成"脉振"高场强,延长了线圈的使用寿命.经实际运行检验,该装置性能稳定,效果好,能耗低,每小时耗电仅0.8 kW,在预磁器领域是一项创新的实用技术.  相似文献   

4.
作为城市污水热能资源化的基础研究,根据理论分析方法,对有效利用城市污水所赋存的热能时,其节能效果和对减轻大气污染的作用进行了若干分析和探讨.分别计算了流量为1 m3/s时城市污水赋存的热量,以及采暖面积为1万m2时所需的城市污水及赋存的热量,与空调、锅炉相比产生相同热量时的一次能和二次能的消减量,以及相应条件下的污染物年间(采暖期)消减量等.  相似文献   

5.
Using the constitutive equation of co-rotational derivative type for anisotropic viscoelastic fluid-liquid crystalline(LC),polymer liquids was developed.Two relaxation times are introduced in the equation:λn represents relaxation of the normal-symmetric stress components;λs represents relaxation of the shear-unsymmetric stress components.A vibrational rotating flow in gap between cylinders with small amplitudes is studied for the anisotropic viscoelastic fluid-liquid crystalline polymer.The time-dependent constitutive equation are linearized with respect to parameter of small amplitude.For the normal-symmetric part of stress tensor analytical expression of the shear stress is obtained by the constitutive equation.The complex viscosity,complex shear modulus,dynamic and imaginary viscosities,storage modulus and loss modulus are obtained for the normal-symmetric stress case which are defined by the common shear rate.For the shear-unsymmetric stress part,two shear stresses are obtained thus two complex viscosities and two complex shear modulus(i.e.first and second one) are given by the constitutive equation which are defined by rotating shear rate introduced by author.The dynamic and imaginary viscosities,storage modulus and loss modulus are given for each complex viscosities and complex shear modulus.Using the constituive equation the rotating flow with small amplitudes in gap between two coaxial cylinders is studied.  相似文献   

6.
玉米中转基因成分的定性PCR检测   总被引:1,自引:0,他引:1  
利用改良 CTAB 法提取玉米产品的基因组 DNA,应用 PCR 检测方法,并以玉米特异性内源基因 IVR 为内参,花椰菜花叶病毒 35S 启动子(CaMV35S 启动子)、农杆茵胭脂碱合成酶终止子(NOS终止子)为靶基因检测玉米中是否存在转基因成分.实验结果表明,有些玉米样品中存在转基因成分,表明市场上存在未经标识的转基因玉米及其加工品.  相似文献   

7.
利用晶体的双折射现象和它的基本性质,采用现代光纤和CCD摄像放大技术手段研究了双偏振光的叠加和干涉现象,讨论了学生在教学中不易理解的难点问题.  相似文献   

8.
科技期刊版式设计略谈   总被引:1,自引:0,他引:1  
对科技期刊版式设计中的标题、插图与空白的处置进行了分析探讨,认为科技期刊版式设计在总体上应是追求格式一致与节奏变化的统一,整体性与连贯性的统一.布局合理的版式设计带给期刊的是整体的和谐美,别具风格的版式设计标志着期刊的个性特征.  相似文献   

9.
对一国或多国军备竞赛的数学模型进行了研究.单独一国的经济增长服从Horrod-Domer模型,但当多国一起竞争时,弱国将遭受前所未有的严重挑战.通过研究超级大国、另一大国和弱国这三个国家之间军备竞赛稳定性问题,得到了军备竞赛稳定性的条件.  相似文献   

10.
Based on the fictitious soil pile model, the effect of sediment on the vertical dynamic impedance of rock-socketed pile with large diameter was theoretically studied by means of Laplace transform technique and impedance function transfer method. Firstly, the sediment under rock-socketed pile was assumed to be fictitious soil pile with the same sectional area. The Rayleigh-Love rode model was used to simulate the rock-socketed pile and the fictitious soil pile with the consideration of the lateral inertial effect of large-diameter pile. The layered surrounding soils and bedrock were modeled by the plane strain model. Then, by virtue of the initial conditions and boundary conditions of the soil pile system, the analytical solution of the vertical dynamic impedance at the head of rock-socketed pile was derived for the arbitrary excitation acting on the pile head. Lastly, based on the presented analytical solution, the effect of sediment properties, bedrock property and lateral inertial effect on the vertical dynamic impedance at rock-socketed pile head were investigated in detail. It is shown that the sediment properties have significant effect on the vertical dynamic impedance at the rock-socketed pile head. The ability of soil-pile system to resist dynamic vertical deformation is weakened with the increase of sediment thickness, but amplified with the increase of shear wave velocity of sediment. The ability of soil pile system to resist dynamic vertical deformation is amplified with the bedrock property improving, but the ability of soil-pile system to resist vertical vibration is weakened with the improvement of bedrock property.  相似文献   

11.
高锰钢的双n行为   总被引:2,自引:0,他引:2  
研究了高锰钢在拉伸过程中形变硬化行为及组织结构变化,结果表明,其真应力,真应变分段符合Hollomon方程,表现为双n行为,高锰钢优异的形变硬化性能表现在n2阶段,为孪晶强化,在位错强化的n1阶段,其形变硬化不显,在拉伸曲线上出现锯齿形状的同时,试样表面也出现平行的痕迹,这两个特点又表明具有面心结构的高锰钢拉伸形变时,似有早为人知的Portevin-Le Chatelier效应。  相似文献   

12.
依据教务管理工作的规律并结合教务管理系统开发的实际经验,介绍了基于校园网的教务管理系统在网络布局和网络技术等方面的设计思想和技术要点,并说明了教务管理系统流程中的各主要系统的地位及作用。  相似文献   

13.
浅谈服务经济时代的高校图书馆读者服务工作   总被引:1,自引:0,他引:1  
读者,作为高校图书馆的服务对象,是高校图书馆活动中最活跃、最重要的因素之一。读者的存在和需求,体现了图书馆存在的社会价值。读者服务永远是高校图书馆工作的主旋律。随着社会的不断发展,创造读者满意的服务环境是高校图书馆所面临的课题和紧迫的战略任务。  相似文献   

14.
结合山地小城镇规划的具体实践,在小城镇城镇性质定位、道路交通规划、村镇中心区详细规划等方面总结经验教训,从总体规划到详细规划各个方面、各个层次提出自己的见解,强调山地小城镇规划中不同于城市规划的特点。  相似文献   

15.
STS教育是目前我国科学教育改革的一种潮流。通过讨论STS教育与科学史之间的关系,结合我国科学教育改革的情况,探讨科学史在STS教育中的重要意义,以及如何应用科学史进行STS教育。  相似文献   

16.
中街是沈阳市唯一的一处重点文物保护区。在进行广泛调查、考证的基础上,详细阐述了中街的形成与发展,对中街建筑的特点进行了分析归纳,并对其建筑保护提出了建设性意见。  相似文献   

17.
JIT采购在医院药品供应中的应用   总被引:2,自引:0,他引:2  
为了解决我国医院用药价格偏高问题 ,必须改变医院传统供应模式。分析了JIT采购模式和传统模式两种医院医药供应模式 ,对比了两种模式的不同 ,指出JIT采购模式的优点 ,并且提出具体实施JIT采购模式的措施  相似文献   

18.
夏季南京市公交空调车空气品质调查分析   总被引:1,自引:0,他引:1  
对南京市目前运行的空调公交车进行了空气品质的调查分析,给出了改善车内空气品质的若干建议。  相似文献   

19.
以实例介绍了空压机车间监控室噪声的综合治理工程.通过对监控室实行隔声,进、出风口消声、空调机向监控室内均匀送风等综合措施,使监控室噪声达到环境排放标准。  相似文献   

20.
拉伸载荷作用下无限大板中三角孔-裂纹问题   总被引:1,自引:0,他引:1  
针对Bueckner原理普遍化,提出了一种求解远方载荷作用下无限大板中孔边裂纹问题的数值方法.通过把适于单一裂纹的Bueckner原理扩充到远方载荷作用下无限大板中孔边裂纹问题,将原问题分解为承受远方载荷不含孔边裂纹的均匀问题和在远方不承受载荷但在裂纹面上和孔的表面上承受面力的问题.算例说明本数值方法对分析无限大板中孔...  相似文献   

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